When Sang Chi was in high school, her teacher frequently asked her parents to come. In order to solve the problem, Sang Chi decided to ask her brother to take the blame. However, the siblings quarreled with each other when they met, so she had no choice but to ask for help from her brother's roommate Duan Jiaxu who came to play at home. Under Sang Chi's pleading and threat, Duan Jiaxu helped Sang Chi go to school to meet the teacher, and the two became friends. Duan Jiaxu treated Sang Chi as his own sister from then on. As Duan Jiaxu graduated from university, the two were separated, and because of some misunderstandings, their relationship became alienated. It was not until Sang Chi, who had grown up, was admitted to Duan Jiaxu's city as she wished, and the two reunited. With increasingly close contact, Sang Chi gradually discovered the source of Duan Jiaxu's pressure. She wanted to protect this big brother who had always been good to her and regain her secret love in her heart. With Sang Chi's company, Duan Jiaxu slowly untied his knot. He really liked the grown-up Sang Chi, and a pure secret love finally blossomed into a beautiful love flower.